We will continue to study prenyltransferase (farnesyl PP) synthetase from the standpoint of mechanism with sulfur and fluorine containing analogues. The relationship of the substrate-binding sites will be probed by competitive binding experiments between farnesyl PP and substrates. The role of metal ions will be examined similarly. A novel prenyltransferase, i.e., geranylgeranyl PP dolichol or undecaprenyl PP synthetase will be purified to homogeneity and characterized for substrate specificity and nature of subunits. The entire terpene biosynthetic pathway in several organisms will be examined. We hope to establish the location of branch points and the regulation of metabolite flow at these branches. The approaches used will involve enzymology, inhibitors, mutants and pulse chase experiments.